It sounds as though the game thinks that your Sim is still married to their former spouse. If that's the case, then removing the married flag should result in removal of the wedding ring.
If you use the Insimenator, I believe its relations changer allows you to set marital status. Or you may be able to use SimPE to edit the Sim Relations between the Sim and their former spouse to be unmarried.
Thanks! I opened their relationship pannels in Sim PE and the "family" boxes were still ticked. I fixed it so hopefully once I go in and reset her it'll be gone. I appreciate the help!